This invention relates to a multicomponent resin composition which undergoes a change in light transmittance with temperature. The resin composition is a blend of at least three kinds of polymers including a combination of two polymers which have mutual solubility and a blend of which exhibits a phase diagram in which a lower critical solution temperature appears.
The recent advancement of optoelectronics is remarkable. It is unquestionable that the role of optoelectronics in the information-oriented society will acquire further growing importance as represented by the rapidly increasing applications of optical fiber communication systems
In utilizing optoelectronics in the information industry an important task is developing suitable materials for information storage. With the rapid development of practical applications of lasers, recently much attention is focused on the so-called thermal-mode storage materials in which thermally written information is stored by a change in a certain physical characteristic of the storage material such as light transmittance or color. As to the form of storage media, optical disc memories are dominant. Current optical disc memories are generally constructed of a glass or plastic substrate and a coating film which is principally formed of an intermetallic compound that undergoes a thermally induced change in its certain optical characteristic such as transmittance, reflectance or refractive index.
In view of the flexibility of organic polymeric materials in various aspects, and particularly in processability, as well as economical advantages of such materials, it is desirable that organic polymeric materials functional as information storage materials should be developed. Until now applications of organic materials to information storage materials for optical memories are limited to auxiliary materials represented by binders some of which include a dye absorbent of laser light. Although some of known organic polymers undergo changes in their certain physical characteristics such as density and refractive index when heated beyond the glass transition temperature or melting point, such polymers do not serve as practical thermal-mode storage materials.